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Horm Metab Res 1992; 24(1): 26-30
DOI: 10.1055/s-2007-1003245
Clinical

© Georg Thieme Verlag, Stuttgart · New York

Peripheral Glucose Metabolism in Patients with Insulin Resistance and Acanthosis Nigricans

M. C. Foss, M. J. A. Saad, G. M. G. F. Paccola, F. J. A. Paula, C. E. Piccinato
  • Department of Medicine, School of Medicine of Ribeirão Preto, São Paulo University, Ribeirão Preto, Brazil
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Publication History

1990

1991

Publication Date:
14 March 2008 (online)

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Summary

The present study was designed to determine forearm muscle glucose uptake and oxidation during the postabsorptive state and after an oral glucose challenge in patients with type A insulin resistance and acanthosis nigricans. Nine normal subjects and six acanthotic patients were studied after an overnight fast (12-14 h) and during 3 hours after ingestion of 75 g of glucose. Peripheral glucose metabolism was analysed by the forearm technique to estimate muscle exchange of substrate combined with indirect calorimetry in forearm.

Two patients (1 and 6) with insulin resistance and acanthosis nigricans had impaired glucose tolerance. All other patients and normals revealed normal glucose tolerance during the tests. Decreased forearm muscle glucose uptake was observed in patients 1 and 6 compared to normal subjects (6.3 and 51.1 vs 127.7 ± 10.1 mg/100 ml forearm·3 h, respectively). Decreased forearm muscle glucose oxidation was also observed in patient 1 as well as in patient 3 who showed normal glucose tolerance. Serum FFA levels were elevated in patient 1 but not in patient 3 and in the other acanthotic patients compared to the normal subjects. Serum insulin levels were significantly higher in acanthotic patients than in normals before and after glucose loading.

The results of the present study revealed that two of six patients with type A insulin resistance and acanthosis nigricans who exhibited glucose intolerance also showed a decrease in peripheral muscle glucose uptake and nonoxidative glucose metabolism. Another patient (3) with normal glucose tolerance showed impaired muscle glucose oxidation but unaltered muscle glucose uptake and nonoxidative metabolism during the 3 hours of study. These data also reinforce the idea that nonoxidative glucose metabolism may play an important role in regulating plasma glucose levels during oral glucose tests.

Key words

Acanthosis Nigricans - Insulin Resistance - Peripheral Glucose Metabolism - Forearm Glucose Uptake - Oxidative Metabolism